A palindrome is a word, phrase, number or any other sequence of units (like a strand of DNA) which has the property of reading the same in either direction (the adjustment of spaces between letters is generally permitted). The word "palindrome" comes from the Greek words palin ("back") and dromos ("racecourse"). Writing literature in palindromes is an example of constrained writing.
The Latin palindrome "Sator Arepo tenet opera rotas" (roughly "The farmer by his labour keeps the wheels to the plough") is remarkable for the fact that it reproduces itself also if one forms a word from the first letters, then the second letters and so forth. Hence it can also be arranged into a square which can be read either horizontally or vertically:
S A T O R
A R E P O
T E N E T
O P E R A
R O T A S
I have no clue what to draw
